Many electrical systems require a fixed and stable supply of electrical energy to operate optimally. One type of electrical system is a computing system. Computing systems typically include a motherboard which may refer to a main circuit board of a computing system. Typically, a motherboard may contain one or more modular or embedded power supplies for supplying power to the various components of a motherboard. Components of a motherboard may include a processor, BIOS, memory, interfaces and controllers which require power to operate.
In an application such as a computing system, a power supply may be a DC/DC power supply and may receive a twelve (12) volt input supply and provide a one (1) volt, three (3) volt or five (5) volt output supply to a power bus. Many components may receive power from the power bus, including active and passive switching devices which create a dynamic load. A dynamic load may be a device or set of devices coupled to the output of a power supply that draws varying current. A dynamic load may create load transients which may inject a disturbance into the power supply. The injection of a disturbance into the power supply may affect the power supply output which may negatively affect performance of components being supplied power through the power bus. For example, a processor is extremely sensitive to an unstable power supply and thus a disturbance will affect operation of the processor and the overall performance of a computing system employing the processor.
In order to ensure optimal performance of a computing system, load dynamics and steady-state performance of a power supply may be tested. However, it is difficult to adequately test the load dynamics and steady-state performance of a motherboard power supply. Conventional power supply testers include large form factor appliances comprising banks of electronic loads. Thus, conventional power supply testers are heavy and cumbersome. Due to their size and form factor, conventional power supply testers require a fixed placement on a work bench. As a result, long supply wires must be utilized to connect the power supply tester to the output terminals of a power supply under test. This reduces performance and quality of the test due to the substantial inductance of the supply wires which limits the external electronic load slew rate (di/dt). A slew rate may refer to a change in output current divided by a rise/fall time. Rise/fall time may refer to an amount of time required to transition between two values of current. Additionally, the load percentage rating and load dynamics (e.g. 0.5 to 50 A/usec) to a power supply module soldered into the motherboard or embedded into the motherboard (the power supply components are soldered into the motherboard) and loaded by circuits on the motherboard at what load currents and at what slew rate is not always known. Thus, a motherboard power supply must be tested while the power supply is soldered to or embedded into the motherboard. Consequently, an improved apparatus and method for testing a power supply is necessary.